This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Gene duplication is a crucial mechanism in the evolution of gene families and genomic structure. Determining the age of gene duplications is important to understanding the relationship between evolutionary events and gene function i modern genomes. Gene duplication dates cannot, in general, be determined directly from sequence because mutation rates are not constant. We can, however, estimate when gene duplications took place by calibrating duplication with respect to speciation events using evolutionary trees. Many studies of gene duplication dating have appeared in the molecular evolution literature. These analyses have been performed by hand. Data sets are growing substantially, so that they are now at the limit of what can be analyzed by traditional methods, and even existing data sets admit alternative hypotheses which would be too tedious to consider without automation. My research involve the design and implementation of algorithms to analyze the history of gene duplication events automatically, providing a building block for large-scale genomic analysis.